1. Field of the Invention
The present invention relates to a method for wrapping pallet loads of goods utilizing heat shrinkable thermoplastic film. Applicants have developed a pallet wrapping system whereby specifically designed individual bags, which have been formed from film stock material which has been highly oriented in a direction which corresponds to the width of the bag in its final form, may be employed to shrink wrap palletized loads. Additionally, it has been found when such bags are constructed in a side-seal, bottom-gusseted, configuration the bag bottom may be easily modified so that when the bag is fitted over the palletized load, the bag bottom which comes into direct contact with the top of the load assumes a generally rectangular configuration, corresponding to the rectangular configuration of the top of the pallet load. Such an arrangement allows the thermoplastic shrouded pallet, when subjected to heat, (a) to shrink in a greater extent around the girth of the pallet by virtue of the higher degree of orientation of the film across the bag width and (b) to generally uniformly conform the rectangular bag bottom with the rectangular top of the pallet load.
2. Description of the Prior Art
In the past a wide variety of heat shrinkable thermoplastic sheet configurations, including bag structures, have been employed to shrink wrap palletized loads of goods. Thermoplastic bags, fabricated from continuous tubes of thermoplastic such as polyethylene, may be used for such shrink-wrap operations. For example, in the past, pallet loads have been enshrouded with plain bottom seal, ungusseted bags and the combination exposed to heat to shrink the bag about the pallet load (see FIG. 10C of the attached drawings). Such an arrangement results in unsightly ears of thermoplastic material projecting from opposite ends of the top of the pallet load. As illustrated in FIG. 10B of the attached drawings, other prior art bag structures employed for this type shrink wrap application included bottom-sealed, side-gusseted bag structures, and even, as shown in FIG. 10A, a tube of thermoplastic, which is gathered and tied together to close one end thereof. In all of such prior art attempts, after heat shrinking of the film enshrouded pallet load, excess film material susceptible of snagging on objects and causing the film covering to be prematurely ripped from the pallet load it protectively encases, was present.